This invention relates in general to a power supply architecture that may be used in a control system comprising one or more microprocessors and, in particular, to a power supply architecture that provides for safety monitoring of the various supply voltages associated with the power supply and/or peripheral components.
In automotive applications, the particular safety standards to which a component or system must adhere are determined by a risk classification scheme known as Automotive Safety Integrity Level (ASIL) and defined by the ISO 26262 Functional Safety for Road Vehicles standard. This classification helps define the safety requirements necessary to be in line with the ISO 26262 standard. The ASIL is established by performing a risk analysis of a potential hazard by looking at the Severity, Exposure and Controllability of the vehicle operating scenario. The safety goal for that hazard in turn carries the ASIL requirements. There are four ASILs identified by the standard: ASIL A, ASIL B, ASIL C, and ASIL D. ASIL D dictates the highest integrity requirements on the product and ASIL A the lowest.
ASIL D refers to the highest classification of initial hazard (injury risk) defined within ISO 26262 and to that standard's most stringent level of safety measures to apply for avoiding an unreasonable residual risk. ASIL D is noteworthy, not only because of the elevated risk it represents and the exceptional rigor required in development, but because automotive electrical, electronic, and software suppliers make claims that their products have been certified or otherwise accredited to ASIL D.